About a month ago, there was a discussion here in which a number of people wanted to try freestyle but found that it crashed on their computers. I contacted the lead developer, Stephan Grabli, and he has made some revisions that should get freestyle to work with most graphics cards. The main problem was with certain ATI cards. I served as a test bed for the revision cycle (the original distribution failed with my card) and a new release works at least on my own computer and, we believe, for most cards. Freestyle’s index site is http://freestyle.sourceforge.net/ . There are links there to downloads, etc.
Freestyle renders 3d scenes in line drawing style. The actual styles of the lines are controlled by Python scripts called style_modules that specify which lines to draw, at what length and how branched, and with what line shaders. The shaders can also be written in Python. Quite a few example style_modules are included with the distribution. Freestyle uses 3ds files for import and the blender 3ds exporter works fine.